Employee Benefit Plans (Narrative) (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Retirement Benefits [Abstract]
Defined Benefit Plan, Plan Assets, Contributions by Employer			$ 1,000,000.0	$ 1,000,000
Defined benefit plan, expected future employer contributions, remainder of fiscal year	$ 0		0
Defined contribution plan, compensation expense	$ 1,000,000.0	$ 900,000	$ 3,000,000.0	$ 2,800,000